/**
 * Copyright (C) 2011 Whisper Systems
 *
 * This program is free software: you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation, either version 3 of the License, or
 * (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program.  If not, see <http://www.gnu.org/licenses/>.
 */
package com.appspot.eusms.util;

import com.appspot.eusms.sms.SmsTransportDetails;

public class CharacterCalculator {

    public CharacterState calculateCharacters(int charactersSpent) {
        int maxMessageSize;

        if (charactersSpent <= SmsTransportDetails.SMS_SIZE) {
            maxMessageSize = SmsTransportDetails.SMS_SIZE;
        } else {
            maxMessageSize = SmsTransportDetails.MULTIPART_SMS_SIZE;
        }

        int messagesSpent = charactersSpent / maxMessageSize;

        if (((charactersSpent % maxMessageSize) > 0) || (messagesSpent == 0))
            messagesSpent++;

        int charactersRemaining = (maxMessageSize * messagesSpent) - charactersSpent;

        return new CharacterState(messagesSpent, charactersRemaining, maxMessageSize);
    }


    public class CharacterState {
        public int charactersRemaining;
        public int messagesSpent;
        public int maxMessageSize;

        public CharacterState(int messagesSpent, int charactersRemaining, int maxMessageSize) {
            this.messagesSpent = messagesSpent;
            this.charactersRemaining = charactersRemaining;
            this.maxMessageSize = maxMessageSize;
        }
    }
}

